Dr.Web anti-virus checker
This add-on will put an end to your doubts. If you're hesitating whether to download a file found on the Internet or not. You have just to check it with this add-on if it's virus-free or if it's infected.
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NoScript
IT blocks Java and javascript form being executed only for trusted websites. It's very effective against XSS attacks (cross-site scripting attacks).
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Mcfee Site advisor
It allows you to identify potentially dangerous websites. Mcfee rely on a bot that download files from websites and check if there are any malware.. It uses a small bar in your browser that turns into green if the site is clean, Yellow: if you have to be careful and RED if the website is potentially dangerous.
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